1. Field of the Invention
The present invention relates to techniques for manufacturing printed circuit boards (PCBs). More specifically, the present invention relates to a method and apparatus for reducing wasted material during the process of manufacturing a PCB panel.
2. Related Art
Electronic devices typically include integrated circuit (IC) chips and other discrete electronic components which are mounted onto one or more printed circuit boards (PCBs). These electronic devices can also include other discrete components, such as a display or a battery, which are not mounted onto PCBs. The PCBs and the other discrete components are then assembled into a housing for the electronic device.
As IC technology continues to evolve, the form factor of electronic devices has decreased. As a result, the process of packaging the PCBs and the discrete components into a housing for the electronic device becomes more difficult. For example, consider a mobile phone which includes a display, a battery, a microphone, a speaker, and an antenna. The microphone and the speaker may be located at opposite ends of the mobile phone, but both components may need to be coupled to digital signal processing (DSP) chip. Similarly, the display may need to be coupled to a graphics chip. Moreover, the DSP and graphics chips may need to communicate with a general-purpose microprocessor chip. Depending on the space constraints of the housing, the chips may be located on different PCBs. In order to facilitate communication between these chips, the PCBs on which these chips reside are electrically connected to each other and the connections between these PCBs must be routed around other discrete components, such as displays, antennas, and batteries.
One solution to this routing problem is to use flexible PCBs. Unfortunately, the cost of manufacturing a rigid-flex PCB can be several times higher than the cost of manufacturing a rigid PCB. This extra cost is typically a function of the complexity of the manufacturing process (e.g., the number of machines and processing steps in the manufacturing process) and the amount of wasted space on the PCB panel. For example, FIG. 1 illustrates a PCB panel 100 which includes rigid PCBs 101-104 and flexible PCBs 105-106. In this system, flexible PCB 105 can be mechanically and electrically coupled to rigid PCB 101 through bond 107 and to rigid PCB 103 through bond 108. Similarly, flexible PCB 106 can be mechanically and electrically coupled to rigid PCB 102 through bond 109 and to rigid PCB 104 through bond 110. As illustrated in FIG. 1, the layout of PCBs 101-106 wastes a substantial amount of material, which cannot be used after the PCBs have been depanelized. For example, FIG. 2 illustrates rigid PCBs 101 and 103, and flexible PCB 105 which have been depanelized from PCB panel 100.
Hence, what is needed is a method and an apparatus for manufacturing a system which includes rigid and flexible PCBs without the problems described above.